package com.atguigu.pratice;

import java.util.Scanner;

public class ThePerfectNum {
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        int n=scanner.nextInt();
        int res=0;
        for(int i=1;i<=n;i++){
            if(isPerfectNum(i)){
                res++;
            }
        }
        System.out.println(res);
    }

    private static boolean isPerfectNum(int i) {
        int sum=0;
        for(int j=1;j<i;j++){
            if(i%j==0){
                sum+=j;
            }
        }
        if(sum==i){
            return true;
        }else{
            return false;
        }
    }
}
